# CVE-2026-80791: nvmet-auth: zero the AUTH_RECEIVE response buffer

> A remote attacker can read uninitialized kernel memory during the NVMe-oF authentication handshake, potentially exposing sensitive data.

- **Severity:** Not scored
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 4 Sep 2026
- **Updated:** 19 Oct 2026
- **Also known as:** AZL-99606, BELL-CVE-2026-80791, DEBIAN-CVE-2026-80791, GHSA-6r74-cc8q-38c5, UBUNTU-CVE-2026-80791

## What is CVE-2026-80791?

CVE-2026-80791 is a vulnerability in Linux, published on 4 Sep 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

In the Linux kernel, the following vulnerability has been resolved:

nvmet-auth: zero the AUTH_RECEIVE response buffer

nvmet_execute_auth_receive() allocates the response buffer with kmalloc()
sized by the host-supplied AUTH_RECEIVE allocation length, but the
DH-HMAC-CHAP builders write only a fixed-size message into it. The full
allocation length is then copied to the wire by nvmet_copy_to_sgl(), so a
remote initiator receives the bytes past the built message -- up to nearly
a page of uninitialized slab -- during the pre-authentication handshake.

Allocate the buffer with kzalloc() so the unwritten tail is zeroed before
it is sent; conforming responses are unaffected.

## Which versions are affected by CVE-2026-80791?


## How do I fix CVE-2026-80791?

Apply the vendor's patch.

## Is CVE-2026-80791 being exploited?

There is no known exploitation of CVE-2026-80791 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-80791 and fix it if it is affected.

What it is: CVE-2026-80791 is a vulnerability in Linux, published on 4 Sep 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2026-80791 in the wild and no public exploit code.

Affected product: Linux. No package-level version data is available, so check the vendor advisory linked from the reference page.

Task:
1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies.
2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it.
3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead.
4. Run the tests and summarise what changed and why.
5. If nothing in the project is affected, say so and change nothing.

Reference: https://insights.sbomify.com/CVE-2026-80791/ (Markdown: https://insights.sbomify.com/CVE-2026-80791/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-80791
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-80791
- OSV: https://osv.dev/vulnerability/CVE-2026-80791

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-80791/
Summaries are generated and may contain mistakes; the official description above is the record.